We'll have to change some stuff that Google deprecated (e.g. the tabs in
the ActionBar) and that requires changing the theme at least in activities.
Since that would look a bit inconsistent we'll change it globally and
use parts of the support library.
While building against this level in general would break our app on
older systems, the NDK will automatically use this level for 64-bit
ABI builds (which are not supported in older levels). So to build
against 64-bit ABIs we have to support this API level.
In Java all integer types are signed, when a negative integer is casted
to a larger type (e.g. int to long) then due to sign extension the upper
bytes are not 0. So writing that value to a byte array does not produce
the expected result. By overloading the putX() methods we make sure to
upcast the values correctly.